ontological argument

One of four traditional lines of reasoning to support the existence of God. Crudely, the argument is that God has all perfections; existence is a perfection, so God exists necessarily. The argument dates back to the 11th-century scholar St Anselm.

In various forms, the ontological argument has been used by René Descartes, Gottfried Leibniz, and Baruch Spinoza, and by several 20th-century philosophers. In the 18th century Immanuel Kant criticized the argument, saying that being or existence is not a property or predicate. The other three traditional arguments are the argument from design, the cosmological argument, and the moral argument.